Method for determining the effects of fancy yarn

ABSTRACT

A method for determining the effects of a fancy yarn by measuring the yarn diameter. The yarn sections between the effect areas are referred to as webs. The effect area is determined in that the beginning of the effect is defined by meeting a first criterion and the end of the effect is defined by meeting a second criterion. A specifiable number of the largest diameters is determined between the beginning and end of the effect, an average is formed from the diameters determined, which is specified as the diameter of the effect, and the effect length is determined from the beginning and end of the effect.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of German patent application10348742.5, filed Oct. 16, 2003, herein incorporated by reference.

BACKGROUND OF THE INVENTION

The invention relates to a method for determining the effects of a fancyyarn, sometimes also referred to as a novelty yarn or an effect yarn, bymeasuring the yarn diameter, wherein the yarn sections between theeffect areas are referred to as webs.

When producing yarn, a uniformity of the yarn, which is as high aspossible, is generally aimed for within narrow tolerances. On the otherhand, the non-uniformity of the yarn is characteristic of fancy yarns. Ayarn, in which thick locations with predetermined larger diameters andwith predetermined lengths, the so-called effects, are present, arereferred to as fancy yarns, also commonly referred to as novelty oreffect yarns. The yarn sections located therebetween with a smallerdiameter are referred to as webs.

It is known to carry out a diameter average value determination at thebeginning of measuring at a spinning station, over the first yarn meter.This so-called reference diameter is the reference diameter for furtherevaluations. In the case of a fancy yarn, a reference diameterdetermined in this manner would be indicated to be thicker owing to thepresence of effects, in other words thick locations, than the thicknessof the web actually is. The recognition of the formation of effects isonly possible on this basis of a simple averaging to an inadequatedegree.

SUMMARY OF THE INVENTION

The object of the invention is to improve the determination of effectsof a fancy yarn.

This object is achieved by a method for determining the effects of afancy yarn by measuring the yarn diameter. The yarn sections between theeffect areas are referred to as webs. According to the invention, theeffect area is determined in that the beginning of the effect is definedby meeting a first criterion and the end of the effect is defined bymeeting a second criterion. A specifiable number of the largestdiameters is determined between the beginning and end of the effect, anaverage is formed from the diameters determined, which is specified asthe diameter of the effect, and the effect length is determined from thebeginning and end of the effect.

Additional advantageous configurations and aspects of the invention aredescribed below.

The method according to the invention makes it possible to recognize theeffects better and to determine the effect diameter, also referred to asthe effect thickness, and the effect length more correctly.

To determine the web diameter D_(ST), an arithmetic average of the yarndiameter is initially formed from a predetermined length of yarn as thereference diameter. The reference diameter is subtracted from theindividual values of the yarn diameter, and the web diameter D_(ST) isthen formed as the arithmetic average from all negative values, whichwere measured adjacent to other negative values. The web diameter, alsocalled the web thickness, as thusly determined is largely uninfluencedby the effects and therefore substantially more accurate than ispossible with the known simple reference value formation in yarnmeasurements. This increased accuracy also has a positive effect on theaccuracy of the effect determination.

The diameter D_(E) of the effect may be formed as an average from thefour largest diameters between the beginning and end of the effect. Itcan be avoided that only a very brief exceeding or falling below of thelimit diameter leads to a falsification of the effect length.

A variation value is advantageously determined, which provides thevariation of the diameter over the effect length. For this purpose, thediameter is continuously measured within the effect length. Thevariation value can be provided as the average quadratic non-uniformitythat provides information about the uniformity of the effect course.Conclusions about the quality of the subsequent end product, for examplea fabric, can be drawn from the variation value. A high uniformityallows a clean image of the effects in the fabric to be expected, alower uniformity, on the other hand, a blurred image. Determination ofthe average quadratic non-uniformity corresponds to the known detectionof the so-called CV value in the case of smooth yarn.

The method according to the invention allows detection of the effectlength and effect thickness with values, which very closely approach thereal configuration and therefore allow reliable information about thequality of the fancy yarn and the end product.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details of the invention can be found in the figures. In thefigures:

FIG. 1 shows a device for carrying out the method according to theinvention,

FIG. 2 shows a fancy yarn, which is shown by arranging measured valuesof the yarn diameter side by side,

FIG. 3 shows a schematic diagram of a yarn effect.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a section of a fancy yarn 1, which runs through a sensor 2,which is provided to measure the yarn diameter D. The sensor 2 is anoptical sensor, as is known in principle, and which will not thereforebe described in detail here. The sensor 2 is connected via a line 3 tothe evaluation unit 4. The evaluation unit 4 determines the desiredeffect data from the measured values of the yarn diameter D transmittedby the sensor 2. The evaluation unit 4 transmits the effect data via theline 5 to an output mechanism comprising a monitor 6. The effect datacan be shown in the desired form on the monitor 6.

The evaluation unit 4 is connected via the lines 7 to further evaluationunits or computers, not shown.

FIG. 2 shows the view of the fancy yarn 1, as measured values arrangedside by side. Effects 8 and webs 9 can be seen but the beginning and endof the effects 8 and the effect thickness or the effect diameter D_(E)and the web thickness or the web diameter D_(ST) cannot be recognizedclearly and therefore not adequately.

The evaluation unit 4 registers the yarn diameter D after 2 mm yarnlength, in each case. A cycle represents a measuring length of 2 mmyarn. In the view of FIG. 3, the yarn diameter D is shown in apercentage over the yarn length L_(G) as a curve 10. The curve 10represents the web diameter D_(ST) in the view of FIG. 3 beginning fromthe left up to the point 11. From the point 11 the curve 10 rises and,at point 12, passes the value of the limit diameter D_(GR). At point 13,the predetermined yarn length L_(V1) has been covered since reaching thepoint 12. After a diameter increase of 15% is registered at point 12,and the exceeding of the limit diameter D_(GR) continues over thepredetermined length L_(V1), for example for six cycles or 12 mm, thepoint 12 is defined as the beginning of the effect. The curve 10 fallsbelow the limit diameter D_(GR) at the point 14. The falling below lastuntil point 15 and therefore over the predetermined yarn length L_(V2).Therefore, the point 14 is defined as the end of the effect. The effectlength L_(E) is determined from the beginning and end of the effectbetween point 12 and point 14. An arithmetic average is formed from thefour largest diameters 16 within the effect. The provision of the effectdiameter is therefore largely independent of the natural diametervariations in the effect area. This arithmetic average is defined as theeffect diameter D_(E).

A variation value, which makes a statement about the quality of theeffects 8 possible, is determined on the basis of the variations of theyarn diameter D, which can be recognized in FIGS. 2 and 3, in the areaof the effect length of the effects 8. The variation value provides theaverage quadratic non-uniformity and is a measure of the uniformity ofthe effect course. The higher the uniformity of the effect course, thebetter the quality of the fancy yarn 1 and the end product producedtherefrom, for example a fabric. The variation value is the relativedispersion of the individual values around the average of the yarndiameter D within the effect length.

Further configurations of the method within the scope of the inventionare possible. The method according to the invention is not limited tothe embodiment shown.

1. Method for determining the effects of a fancy yarn by measuring theyarn diameter, wherein the yarn sections between the effect areas arereferred to as webs, characterized in that the effect area is determinedin that the beginning of the effect is defined by meeting a firstcriterion and the end of the effect is defined by meeting a secondcriterion, in that a specifiable number of the largest diameters isdetermined between the beginning and end of the effect, in that anaverage is formed from the diameters determined, which is specified asthe diameter of the effect, and in that the effect length is determinedfrom the beginning and end of the effect.
 2. Method according to claim1, characterized in that the web diameter D_(ST) is determined, in orderto determine the relative effect thickness.
 3. Method according to claim1, characterized in that to determine the web diameter D_(ST), anarithmetic average of the yarn diameter is initially formed from apredetermined length of yarn as the reference diameter, in that thereference diameter is subtracted from the individual values of the yarndiameter, and in that the web diameter D_(ST) is then formed as thearithmetic average from all negative values, which were measuredadjacent to other negative values.
 4. Method according to claim 1,characterized in that the diameter D_(E) of the effect is formed as anaverage from the four largest diameters between the beginning and end ofthe effect.
 5. Method according to claim 1, characterized in that theexceeding of a limit diameter D_(GR) applies as the first criterion,which diameter is greater by a defined amount than the web diameterD_(ST) and in that the exceeding lasts over a predetermined yarn lengthL_(V1) and in that the falling below of the limit diameter D_(GR)applies as the second criterion and the falling below lasts over apredetermined yarn length L_(V2).
 6. Method according to claim 5,characterized in that the limit diameter D_(GR) is 15% greater than theweb diameter D_(ST).
 7. Method according to claim 5, characterized inthat the predetermined yarn length is then taken to be reached when thecriterion is met over six consecutive measured values.
 8. Methodaccording to claim 1, characterized in that a measured value is detectedevery two millimeters when measuring the yarn diameter.
 9. Methodaccording to claim 1, characterized in that the variation in thediameter is determined on the effect length.
 10. Method for determiningthe effects of a fancy yarn by measuring the yarn diameter, wherein theyarn sections between the effect areas are referred to as webs,characterized in that the effect area is determined in that thebeginning of the effect is defined by meeting a first criterion and theend of the effect is defined by meeting a second criterion, in that aspecifiable number of the largest diameters is determined between thebeginning and end of the effect, in that an average is formed from thediameters determined, which is specified as the diameter of the effect,and in that the effect length is determined from the beginning and endof the effect, the method being characterized in that the exceeding of alimit diameter D_(GR) applies as the first criterion, which diameter isgreater by a defined amount than the web diameter D_(ST) and in that theexceeding lasts over a predetermined yarn length L_(V1) and in that thefalling below of the limit diameter D_(GR) applies as the secondcriterion and the falling below lasts over a predetermined yarn lengthL_(V2).
 11. Method according to claim 10, characterized in that thelimit diameter D_(GR) is 15% greater than the web diameter D_(ST). 12.Method according to claim 10, characterized in that the predeterminedyarn length is then taken to be reached when the criterion is met oversix consecutive measured values.